Every year, plenty of UK smokers put off quitting until their symptoms feel impossible to ignore. The trouble is, by the time some signs are hard to miss, real damage may already have been done.
Spotting the early warning signs, like a cough that won't shift, getting out of breath on the stairs or changes in the mirror, can be one of the strongest reasons to quit sooner rather than later.
Effective stop smoking treatments are available, and some of the health benefits of quitting start within days. Here are five signs that smoking is already affecting your body, and that now's a good time to act.
You don't have to wait for years to feel a difference. Some benefits of stopping show up within days.
1. You have a persistent cough
A cough that won't go away is one of the most common signs that smoking is affecting your lungs. The harmful chemicals in smoke can damage the lining of your lungs and airways.1
“You do not need to wait for symptoms before stopping smoking: the benefits begin soon after you quit. If you already have a persistent cough or worsening breathlessness, arrange a medical assessment too. A cough lasting more than three weeks needs checking, even if you think smoking explains it.
Ana Carolina GoncalvesSuperintendent Pharmacist
Many smokers write this off as just a "smoker's cough". But a persistent chesty cough with phlegm is one of the main symptoms of chronic obstructive pulmonary disease (COPD).2
COPD is the name for a group of long-term lung conditions, including chronic bronchitis and emphysema.2 The damage it causes is permanent, but treatment can help slow it down.2 Smoking is the main cause, and it's thought to be behind around 9 in every 10 cases.1
The NHS advises seeing a GP if you have persistent symptoms of COPD, particularly if you're over 35 and smoke or used to smoke.2 A simple breathing test can help diagnose it, so treatment can start before your lungs become badly damaged.2
You don't need to wait for a diagnosis to get a cough checked. See a GP if you've had a cough for more than three weeks.3
Coughing up blood needs prompt attention. For a few small spots or streaks, ask for an urgent GP appointment or contact NHS 111.4 Call 999 or go to A&E if it's more than a few spots or streaks, or if you're also struggling to breathe, have a very fast heartbeat or pain in your chest or upper back.4
Any blood when you cough needs an urgent check. More than a few streaks, or blood with chest pain or breathlessness, is an emergency.
If you have COPD and you smoke, stopping is the most important thing you can do.2
2. You get breathless more easily than you used to
Getting short of breath on the stairs, walking quickly or doing things that used to feel easy is worth taking seriously. Many smokers put it down to being unfit. But shortness of breath, particularly when you're active, is one of the main symptoms of COPD.2
COPD happens when your lungs and airways become inflamed, damaged and narrowed.1 Many people don't realise they have it, and the breathing problems tend to get worse over time.2
Breathlessness can also come from the effects of smoking on your heart and blood vessels. Carbon monoxide from cigarette smoke stops your blood carrying oxygen around your body properly, so your heart has to work harder.5
Severe difficulty breathing, or a chest that feels tight or heavy, needs emergency help. Call 999 or go to A&E straight away.6
Gasping for breath, or a tight, heavy feeling in your chest? Do not wait to see if it passes. Call 999.
Quitting starts to ease both burdens. Within days, carbon monoxide and oxygen levels in your blood return to normal. Within weeks, your lung function improves and you get less coughing and shortness of breath.7
3. Your skin has changed
The effect of smoking on your skin is a visible sign of damage that's often happening elsewhere in your body too.
Smoking narrows the blood vessels near the surface of your skin. That reduces blood flow and the oxygen and nutrients reaching it.8 It also increases an enzyme that breaks down collagen, the protein that keeps skin smooth and supple.8
Several studies have found that smoking is a risk factor for early facial wrinkles, and the more you smoke, the greater the risk. Smokers in their 40s often have as many facial wrinkles as non-smokers in their 60s.8
Skin damaged by tobacco smoke typically looks greyish. Damage can be happening before you can see it, and it can start to be detected in your 20s or 30s.8
The changes in the mirror are a useful nudge. What's happening to your skin is happening to blood vessels elsewhere too.
The good news? Once you quit, more oxygen gets to your skin, making it look brighter. Your teeth also stop getting stained with tar.9
4. You notice signs of poor circulation
Cold hands and feet, slow-healing cuts or numbness in your legs can be signs that your circulation isn't as good as it should be.
The chemicals in cigarettes make the walls of your arteries sticky, so fatty material builds up on them. Over time, this can clog your arteries and reduce the space for blood to flow.5 If it affects the arteries to your heart or brain, it can lead to a heart attack or stroke.5
Even people who smoke fewer than five cigarettes a day can have early signs of heart and circulation disease.10
When the arteries to your legs are affected, it's called peripheral arterial disease (PAD). Signs include leg pain when walking that eases with rest, legs and feet that feel cold or numb, and sores on your legs or feet that don't heal.11
Leg pain when you walk, or sores on your feet that won't heal? See a GP, as these can be signs of PAD.
Quitting brings better blood circulation to your heart and muscles.9 Within a year of stopping, your risk of coronary heart disease is cut by half.7
5. You're experiencing erectile dysfunction
Erectile dysfunction (ED) in men who smoke can often be linked to blood flow.
An erection depends on healthy blood vessels carrying enough blood to the penis. Smoking damages blood vessels, and it's a known cause of ED.5,10
ED can also be an early warning sign for your heart. In one large US study, men with ED were more likely to go on to have heart and circulation problems, even after other risk factors were taken into account.12 If erection problems keep happening, see a GP.13 It's a chance to check your heart health too.
ED can be an early warning sign for your heart. It's worth a check-up, not just a prescription.
Stopping smoking is one of the lifestyle changes that can help with ED.13 If you're ready to quit, a licensed stop smoking treatment such as varenicline can help.14
Through Pharmica, the varenicline consultation checks your mental health history, medical conditions and medicines. New treatment starts with a two-week starter pack, begun 1 to 2 weeks before your quit date. Follow its advice on stopping and getting help if you have serious symptoms.
Frequently asked questions
What happens when you stop smoking?
Your body starts to repair itself straight away. Within days, carbon monoxide and oxygen levels in your blood return to normal, and your taste and smell improve. Within weeks, your lung function improves and you cough less. Within a year, your risk of coronary heart disease is cut by half. After 10 years, your risk of dying from lung cancer falls to half that of a smoker.
What are the symptoms of stopping smoking?
Withdrawal symptoms happen because your body has got used to nicotine. Common ones include cravings, irritability, restlessness, trouble concentrating, poor sleep and feeling anxious or low. They're usually strongest in the first week, especially the first three days, and last three to four weeks on average. Stop smoking medicines and nicotine replacement can make them easier to manage.
How long does it take for smoking cravings to stop?
Withdrawal, including cravings, is usually strongest in the first three days and lasts three to four weeks on average. Some people get cravings for longer, sometimes a few months, often triggered by habits or places linked to smoking. Having a plan for those moments helps, and combining a stop smoking medicine with nicotine replacement makes you much more likely to quit for good.
Can you reverse the damage smoking causes to your lungs?
Partly. After you quit, your lung function improves and you cough and wheeze less. But if you already have COPD, the damage to your lungs is permanent. Stopping smoking is still the most important thing you can do, as it helps stop the condition getting worse. If you're breathless or have a cough that won't go away, ask your GP about a breathing test.
Is it ever too late to benefit from quitting smoking?
No. Quitting improves your health whatever your age and no matter how long you've smoked. Within a year, your risk of heart attack halves compared with a smoker's. After 10 years, your risk of dying from lung cancer falls to half that of a smoker. Breathing, energy and circulation often improve too. The sooner you stop, the more you're likely to benefit.
References
- NHS. Chronic obstructive pulmonary disease (COPD): Causes. NHS website; 2023. nhs.uk
- NHS. Chronic obstructive pulmonary disease (COPD). NHS website; 2023. nhs.uk
- NHS. Cough. NHS website; 2023. nhs.uk
- NHS. Coughing up blood (blood in phlegm). NHS website; 2024. nhs.uk
- British Heart Foundation. Smoking and your heart. British Heart Foundation; 2026. bhf.org.uk
- NHS. Shortness of breath. NHS website; 2024. nhs.uk
- NHS inform. Benefits of stopping smoking. NHS 24; 2026. nhsinform.scot
- Action on Smoking and Health. How smoking affects the way you look. ASH; 2026. ash.org.uk
- NHS. Benefits of quitting smoking. Better Health, NHS website; 2026. nhs.uk
- Oxford Health NHS Foundation Trust. Quit smoking. Oxford Health NHS Foundation Trust; 2024. oxfordhealth.nhs.uk
- NHS. Peripheral arterial disease (PAD). NHS website; 2026. nhs.uk
- Uddin SMI, Mirbolouk M, Dardari Z, et al. Erectile Dysfunction as an Independent Predictor of Future Cardiovascular Events. Circulation. 2018;138(5):540-542. doi:10.1161/CIRCULATIONAHA.118.033990
- NHS. Erectile dysfunction (impotence). NHS website; 2023. nhs.uk
- Brown & Burk UK Ltd. Varenicline 1 mg film-coated tablets: Summary of Product Characteristics. Electronic Medicines Compendium; 2026. medicines.org.uk/emc
This article is intended for informational purposes only and does not replace professional medical advice. Always read the patient information leaflet supplied with your medication and speak to a healthcare professional if you have specific concerns.